Materials often are added to flowing fluids in order to reduce the energy lost due to friction, or drag, thus permitting the movement of more fluid at the same differential pressure. Materials for reducing drag in flowing fluids generally are known by the generic names “flow improver” or “drag reducer additive” (sometimes referred to as “DRA”).
Unfortunately, the DRA in liquid hydrocarbon fuels has the potential to cause a number of problems. Methods are needed to improve the performance of engines that use liquid hydrocarbon fuel otherwise contaminated with DRA.